OS SIERRA VERY SLOW AFTER SHORT BREAK

Hi everyone,

Working on a Mac Pro 2012, system OS Sierra. And noticed a strange behavior. Every time I take a short break from working on my mac (about 5 min or so) the system becomes very dodgy.

For about 30sec up to a minute, the actions I do are coming with some sort of latency/delay. Than suddenly the computer takes up again and everything seems OK.

In the period of dodgyness, forcing the system results in a panic kernel. The only thing I can do is to be patience for my system to come up again. Rather annoying.

Does anyone of you struggles with the same issue? But more important... What is this and what can I do about it.

THX

B&